(a) Field of the Invention
The present invention relates to a method of compensating for noise in a lane drifting warning system, and more particularly to a method of compensating for peripheral environment data noise in road image signal data of a lane drifting warning system for vehicles.
(b) Description of the Related Art
A conventional lane drifting warning system, with reference to FIG. 1, comprises a camera 10 such as a concatenated disk (CCD) camera for collecting images of lane markers and outputting corresponding image signals; an electronic control unit (ECU) 11 for receiving the image signals output from the camera 10, processing the image signals using a pre-installed program to determine if the vehicle is veering from the lane it is in, and outputting alarm signals if it is determined that the vehicle is drifting out of the lane; and alarm unit 12 for outputting an alarm to alert the driver if the alarm signals are output from the ECU 11.
In such a lane drifting warning system, the most important requirements are precision and speed. That is, the system must be able to precisely determine if the vehicle is drifting out of the lane (i.e., precisely extract vehicle lane marker information), and quickly alert the driver if the vehicle is veering from within the lane.
However, in the conventional system, the image signals output by the camera 10 include peripheral environment noise. This is particularly problematic, with reference to FIG. 2, in portions of the image signals corresponding to sections 1 and 2. As a result, noise is extracted together with the lane markers such that the precise extraction of the same is not possible. Further, such peripheral environment noise slows the overall process of extracting the lane markers such that a delay occurs in alerting the driver of lane drifting.
The present invention has been made in an effort to solve the above problems.
It is an object of the present invention to provide a method of effectively compensating for peripheral environment data noise in road image signal data of a lane drifting warning system for vehicles such that lane marker extraction is performed accurately and in a timely manner.
To achieve the above object, the present invention provides a method of compensating for noise in a lane drifting warning system. The method includes the steps of converting input image signals into binary data; determining if the converted image signals are those from a start of a lane detecting process; reading previously stored data of the slant in the lane markers if it is determined that it is not the start of the lane detecting process; compensating for peripheral environment noise in the slant in the lane markers; extracting portions of the signals determined to be possible indications of road lane markers if it is determined that it is the start of the lane detecting process; extracting actual lane marker portions from the portions of the signals determined to be possible indications of road lane markers; measuring and storing a slant in the lane markers; calculating a width of a lane defined by the lane markers and determining if the vehicle is veering from the lane; and outputting a warning to alert the driver if the vehicle is veering from the lane.
According to a feature of the present invention, the step of compensating for peripheral environment noise in the slant in the lane markers, the slant in the lane markers is converted by adding to the slant a value equal to the amount of noise in the image signals to compensate for the noise.